Lactic Acid Concentration Research Articles

The Potential of Co-Fermentation of Whole-Plant Cassava with Piper sarmentosum: A Comprehensive Study of Fermentation Quality, Antioxidant Activity, Bacterial Community Structure, and Microbial Ecological Networks in Novel Foods.

The objective of this study was to explore the preservation of food products through the co-fermentation of whole-plant cassava and Piper sarmentosum (PS) without additives. We assessed fermentation quality, antioxidant activity, bacterial community structure, function profile, and microbial ecological network features. Our results demonstrate that co-fermentation of whole-plant cassava with 10% PS significantly improves food quality. The co-fermented samples exhibited enhanced lactic acid concentrations and increased antioxidant activity, with reduced pH values and concentrations of acetic acid, butyric acid, and ammonia-N(NH3-N) compared to whole-plant cassava fermented alone. In addition, PS addition also optimized microbial community structure by elevating the total abundance of lactic acid bacteria and influenced bacterial predicted functions. Furthermore, our analysis of co-occurrence networks reveals that co-fermentation impacts microbial network features, including module numbers and bacterial relative abundances, leading to altered complexity and stability of the networks. Moreover, out study also highlights the impact of ferment undesirable bacteria like Pseudomonas aeruginosa and unclassified_Muribaculaceae playing crucial roles in microbial network complexity and stability. These findings provide valuable insights into the anaerobic fermentation process and offers strategies for regulating food fermentation quality.

Cross-kingdom regulation of ginseng miRNA156 on immunity and metabolism

Aim of the studyTo study the cross-border regulation of immunity and energy metabolism by ginseng miRNA156, and to provide a new perspective for further exploring the possibility of ginseng miRNA156 as a pharmacodynamic substance. Materials and methodsCombined with the previous research results of our research group, miRNA156 with high expression in blood sequencing of intragastrically administered with ginseng decoction was selected. Bioinformatics analysis was performed on the selected differential miRNA156. The target genes of differential miRNA156 were mainly enriched in metabolic, immune and other signaling pathways. According to the analysis results, the experimental part will use qi deficiency fatigue model and RAW264.7 cells. The contents of lactic acid (LA), creatine kinase (CK), blood urea nitrogen (BUN), lactate dehydrogenase (LD), liver glycogen (LG), muscle glycogen (MG), interleukin 4 (IL-4), matrix metallo-proteinase 9 (MMP-9), superoxide dismutase (SOD), malondialdehyde, phosphor-enolpyruvate carboxykinase (PEPCK), glucose-6-phosphatase (G6pase), nitric oxide (NO) and tumor necrosis factor-α (TNF-α) were measured after administration of miRNA156. ResultsGinseng miRNA156 can accelerate the removal of metabolic waste during exercise. Increase the glycogen reserve in, provide energy for the body, regulate the activity of key gluconeogenesis enzyme phosphorus, improve the energy metabolism system of, and enhance the endurance of fatigue mice. The contents of matrix metalloproteinase 9, superoxide dismutase and malondialdehyde were affected, and the content of TNF-α in the supernatant of RAW264.7 cells was significantly increased, which had certain antioxidant capacity and potential immunomodulatory effects. ConclusionGinseng miRNA156 has a certain regulatory effect on the energy metabolism and immune function of mice, which makes it possible to regulate the cross-species regulation of ginseng miRNA in theory, provides ideas for ginseng miRNA to become a new pharmacodynamic substance.

Effect of distillery wastewater on chemical composition and microbial community of Sorghum propinquum silage during micro-permeation of air

The aim of this study was to investigate the effect of distillery wastewater (DWW) on the nutrient composition, fermentation quality and microbial community of Sorghum propinquum silage during the micro-permeation of air. S. propinquum without (CK) or with L. buchneri, (LAB), distillery wastewater yellow serofluid (Y) and distillery spent wash (S) was ensiled for 60 days, and then subjected to a micro-permeation stability of air test for 6 days. After 60 days of storage, treatments with DWW and LAB decreased the loss of DM, inhibited the degradation of protein and reduced the production of ammonia nitrogen in silage relative to the control. In particular, S. propinquum silage treated with yellow serofluid sustained higher levels. Moreover, the addition of DWW resulted in higher levels of acetic and propionic acid than the other treatments. During the micro-permeation of air, the addition of DWW was effective in inhibiting the reduction of lactic acid content, and unique genera Roseburia and Faecalibacterium, which are beneficial for livestock production, discovered in DWW-treated S. propinquum silage. In conclusion, the addition of DWW was efficacious in improving the nutritional composition and microbial community of S. propinquum silage during the micro-permeation of air.

Screening of Lactic Acid Bacteria for Silage Inoculant Candidate

Abstract Silage fermentation is generally assisted by lactic acid bacteria (LAB). The aim of this study was to screen selected LABs for silage inoculant. A total of 60 LAB isolates from the Indonesian Culture Collection (InaCC) were used in this study. Screening was carried out in an MRS broth medium using three different substrates, which were glucose, sucrose, and carboxyl methyl cellulose (CMC). The supernatant from LAB cultures was tested for pH, lactic acid (LA) concentration, antimicrobial activity, and cellulolytic activity. The results of the screening obtained 4 LAB isolates to be used as silage inoculant. Three LAB isolates selected from the glucose substrate were Lactobacillus fermentum InaCC-B1024, Lactobacillus plantarum InaCC-B1028, and L. brevis InaCC-B1052. Lactobacillus fermentum InaCC B1024 has a pH, LA concentration, cellulolytic activity, and percentage inhibition of 3.71, 318.931 mM, and 0.806 U/mL, > 95% antibacterial inhibition against B. subtilis, S. auerus, K. michiganensis, S. lloydii, and S. gallinarum, and <35% antifungal activity against M. ramosissimus, A. flavus, F. oxysporum, and P. griseofulvum, respectively. L. plantarum InaCC-B1028 has a pH, LA concentration, cellulolytic activity, and percentage activity of 3.61, 318.833 mM, 0.866 U/ml, > 95% antibacterial activity against B. subtilis, E. coli, M. luteus, S.auerus, K. michiganensis, S.lloydii, S. gallinarum, and < 40% antifungal activity against M. ramosissimus, A. flavus, F. oxysporum, and P. griseofulvum, respectively. L. brevis InaCC-B1052 has a pH, LA concentration, cellulolytic activity, and percentage activity of 3.67, 301.676 mM, no cellulolytic activity, > 95% antibacterial activity against E. coli, M. luteus, S. auerus, K. michiganensis, S. lloydii, S. gallinarum, and < 25% antifungal activity against M. ramosissimus and A. flavus, respectively. One LAB isolate selected from sucrose was L. kimchii InaCC-B982. Its pH, LA concentration, cellulolytic activity, and percentage activity were 3.77, 285.5 mM, 7.288 U/mL, > 95% antibacterial activity against E. coli, M. luteus, S. auerus, K. michiganensis, S. lloydii, S. gallinarum, and <15% antifungal activity against M. ramosissimus, A. flavus, F. oxysporum, and P. griseofulvum, respectively. Based on the results, the four LABs could be used as silage inoculant candidates.

Special circular style exercises within certain physiological and performance indicators for the young freestyle wrestler’s Abbasid grip

The research focused on developing circular style exercises for young wrestlers and the effect of such exercises upon some physiological indicators such as heart rate, O2 saturation, and lactic acid concentration. the researcher made use of the training approach according to the circular training method. The researcher applied the items of exercise according to the circular method for a period of (8) weeks, with (3) training units per week. Exercises were performed based on the circular method and its effect on physiological capabilities such as heart rate, O2 saturation, lactic acid concentration, and the result of the efficiency of exercises in the circular method according to the method prepared. The physiological variables witnessed the improvement of the performance level in the post-tests of the control and experimental groups as a result of the increase in retention of the increase in the adaptations resulting from the effectiveness of the program which the performance of the Abbasid grip for the wrestlers according to the training program. The researcher arrived at the conclusion that, given the research variables being investigated, the experimental group was superior than the control group. Additionally, it was shown that this strategy resulted in an increase in retention and a decrease in loss in proportion to the adaptations. In order to prevent faults in the training unit for the experienced in the sample.

Probiotic Growth Pattern and Physicochemical Evaluation of Water Kefir Fermentation

Probiotics are live-friendly microorganisms that can confer a health benefit on the host if it is consumed in sufficient amounts. Water kefir is a probiotic-rich fermented beverage that contains multi-species of live cultures. Brown sugar and palm sugar were used for water kefir fermentation due to their high sucrose and mineral contents. The objective of this study was to determine the probiotic growth pattern of water kefir and to evaluate the physicochemical parameters, including the pH changes, lactic acid content, reducing sugar content, and total soluble solids. The fermented water kefir was collected at every 6-hour interval, until the end of 72 hours of fermentation. The growth curve was determined by enumerated probiotics on De Man, Rogosa, and Sharpe (MRS) agar, Yeast Extract-Peptone-Dextrose (YPD) agar, and Gluconobacter (GM) agar plates, respectively. MRS, YPD, and GM agar plates were used to enumerate lactic acid bacteria, yeast, and acetic acid bacteria, respectively. The result showed increased probiotic growth as fermentation time increased with different phases observed from the growth curve. The stationary phase of probiotics was recorded at 30-42 h and was recommended as the optimal harvesting point. Besides, longer fermentation time produced lower pH values and lower total soluble solids while higher lactic acid and higher reducing sugars. At the end of fermentation, the concentration of lactic acid and reducing sugars were 2.16 ± 0.09 g/L and 13.66 ± 0.14 mg/mL, respectively. In conclusion, probiotics from water kefir fermentation are suggested to be best harvested between 30-42 hours and can be used for self-consume or downstream processing.

Silage Quality Characteristics of Quinoa Varieties Grown in Different Row Spacings

Changing climatic conditions, agricultural lands becoming barren, losing their qualities and decreasing feed resources have led to the search for alternative feed resources. Quinoa (Chenepodium quinoa Willd.) is increasing in importance as an alternative feed source because it is a plant resistant to arid, salty and cold conditions. Quinoa plant can be considered as an alternative plant for silage, which is an important feed source for animals. In this study, the effects of sowing Cherry Vanilla and Read Head quinoa varieties at 4 different row spacings (17.5, 35.0, 52.5, 70.0 cm) on silage quality were investigated. In the research, pH, dry matter ratio, fleig score, ammonia production, sensory analyses, lactic acid, acetic acid, propionic acid and butyric acid contents of quinoa silage were determined. While the effect of row spacing on dry matter ratio, ammonia production, sensory analysis, lactic acid, acetic acid, propionic acid and butyric acid ratios was found to be significant, its effect on pH value was insignificant. The quinoa varieties used in the research had a significant effect on the dry matter ratio and propionic acid content. In the light of the results obtained from the research, it was concluded that in order to obtain a quality quinoa silage, the plants should be sown in 52.5 cm row spacing and the Cherry Vanilla variety should be preferred.

Karakteristik Kimia Dan Akseptabilitas Set Yogurt Jambu Biji Merah (Psidium guajava L) Dengan Variasi Waktu Inkubasi

Red guava has high levels of vitamin C among other fruits such as papaya and Siamese oranges which can be used as a source of vitamin C requirements and has a distinctive color. This research aims to determine the length of incubation time and the comparison of the concentration of red guava juice with cow's milk on the chemical characteristics and acceptability of the yogurt set, comparing it with SNI Yogurt and determining the best chemical characteristics and acceptability. The experimental design used was a descriptive method by calculating the average value and standard deviation with treatment A1 = (50% cow's milk: 50% red guava juice), A2 = (60% cow's milk: 40% red guava juice), and A3 = (40% Cow's milk: 60% Red guava juice) for incubation time treatment B1 = (4.5 hours), B2 = (5.5 hours), B3 = (6.5 hours), and B4 = (7.5 hours). The results showed that the length of incubation time and the ratio of concentrations of red guava juice to cow's milk had an effect on chemical characteristics and acceptability. The lactic acid content produced is in accordance with the 2009 SNI yogurt range, namely 0.5-2.0% and acceptability of sour/distinctive taste, normal/distinctive aroma and thick liquid texture. Treatment A3 (40% cow's milk: 60% red guava juice) B2 (incubation time 5.5 hours) produced chemical characteristics (lactic acid content 0.88% and vitamin C content 152.84 mg/100g) and the best acceptability with a color hedonic value of 4 .24 (neutral), taste 3.92 (neutral), aroma 3.40 (neutral), texture 3.64 (neutral) and total acceptance 3.28 (somewhat like).

Pengaruh Jenis Gula dan Waktu Fermentasi Terhadap Kualitas Minuman Fermentasi Kombucha Air Kelapa

Coconut water is rich in nutrients in the form of sugar, protein, fat, electrolytes, growth hormones and is relatively good for developing bacterial growth to produce other food products. As a diversification of coconut water waste, coconut water is processed into a fermented coconut water kombucha drink. This research aims to determine the effect of the type of sugar and fermentation time on the quality of the fermented coconut water kombucha drink by varying the type of sugar, namely: (cane sugar; palm sugar and coconut sugar) and varying the fermentation time 3;6;9;12 and 15) day. After obtaining the fermented coconut water kombucha drink, analysis was carried out to obtain the best coconut water kombucha. The tests carried out included lactic acid tests, Vitamin C levels, pH variance ANOVA tests kombucha was palm sugar type coconut water kombucha and a fermentation time of 15 days with a lactic acid content of 3.6302% and a Vitamin C content of 0.3052, pH 3.2 and the organoleptic test results had an average color, aroma , and taste of 3.1.

Effect of salt concentration on the quality and microbial community during pickled peppers fermentation

This work aimed to investigate the effect of salt concentration on the quality and microbial community of pickled peppers during fermentation, and the cross-correlation between microorganisms and quality was also revealed. The results showed that 9 volatile flavor compounds were unique to the low salt concentration group (D group), which also contained higher content of FAA, lactic acid and acetic acid than high salt concentration group (G group). Meanwhile, the samples of D2 group have a better texture properties. Firmicutes, Proteobacteria, Ascomycota, Lactobacillus, Pectobacterium, and Pseudomonas were detected as the main microbial community during the fermentation with different salt concentrations. Furthermore, the correlations analysis results indicated that the salt concentration has a significant effect on the microbial community of pickled peppers (p < 0.001), and Pediococcus, Lactobacillus, Cedecca, Issatchenkia, Pichia, Kazachstania, and Hanseniaspora were significantly correlated with flavors, which played crucial roles in the unique flavor formation of pickled peppers.

Effects of Konjac Glucomannan and Its Oligosaccharides on Improvement of Lactose Intolerance as Gut Prebiotics.

Lactose intolerance (LI) is a widespread health issue affecting almost 70% of the world population. This study evaluates the potential prebiotic benefits of konjac glucomannan (KGM) and konjac oligogalactomannan (KOGM) in improving LI. Colonic fermentation results indicate that lactase groups of healthy subjects showed lower pH, higher lactic acid content, and lactase activity in fermentation broth compared with LI subjects. Total short-chain fatty acid (SCFAs) content reached 1.71 mmol/L in healthy subjects, whereas it was 1.49 mmol/L in LI subjects. In vivo studies demonstrated that KGM and KOGM intake reduced total cholesterol (T-CHO) and triglyceride (TG) levels in the liver and significantly increased immunoglobulin G (lgG) and immunoglobulin A (lgA) values, while KOGM inclusion led to a significant 23.04% increase in serum free fatty acid (FFA) levels compared to the Blank group (p < 0.05). Furthermore, ileal tissue analysis revealed a marked increase in villus height and intestinal wall thickness (p < 0.05) as well as a decrease in crypt depth (p < 0.05). The composition and proportion of gut microbiota have improved with KGM and KOGM use, notably increasing the abundance of Lactobacillus and Lachnospiraceae_NK4A136_group, respectively (p < 0.05). Compared with the Blank group, Lactobacillus abundance increased by approximately 25.82% in the Drug group, 18.23% in the KGM group, and 8.67% in the KOGM group. These findings suggest that KGM and KOGM can be utilized as prebiotics to alleviate LI symptoms.

Effect of heat-reinforcing needling on hypoxia-inducible factor 1α and glycolysis activity in rabbits with cold syndrome of rheumatoid arthritis.

To observe the effect of heat-reinforcing needling (HRN) on synovial inflammation, hypoxia-inducible factor-1α (HIF-1α) and glycolytic activity in serum and synovial tissue in rabbits with cold syndrome of rheumatoid arthritis (RA), so as to explore its mechanisms underlying improvement of RA. A total of 32 rabbits were randomly divided into normal, model, inhibitor and HRN groups, with 8 rabbits in each group. The RA with cold syndrome model was induced by injecting ovalbumin dry powder and Freund's complete adjuvant combined with cold freezing. Rabbits in the inhibitor group were intraperitoneally injected with 2-methoxyestradiol (2.5 mg/kg), rabbits in the HRN group were received HRN at bilateral "Zusanli" (ST36) for 30 min. The treatments were conducted once daily for 14 consecutive days. After the interventions, the knee circumference and pain threshold were measured. The contents of nicotinamide adenine dinucleotide phosphoric (NADPH), Hexokinase II (HK2) and 6-phosphofructo-2-kinase/fructose-2, 6-biphosphatase 3 (PFKFB3) in serum of rabbits were detected by ELISA. The pathological morphology of synovial tissue of the knee joints were observed by HE staining. The positive expressions of tumor necrosis factor (TNF-α), interleukin (IL)-1β, IL-6 and IL-17 in synovial tissue of knee joint were detected by immunohistochemistry. The content of lactic acid in synovial tissue of rabbit knee joint was detected by spectrophotometry. The expression levels of HIF-1α, pyruvate kinase 2 (PKM2) and lactate dehydrogenase (LDHA) in synovial tissue of knee joint were detected by Western blot. After intervention, compared with the normal group, the knee circumference was significantly enlarged (P<0.05), the pain threshold was significantly decreased (P<0.05)；the synovial tissue of knee joints showed significant cell proliferation and inflammatory infiltration, the pathological score was significantly increased (P<0.05)；positive expressions of TNF-α, IL-1β, IL-6 and IL-17, the content of lactic acid in synovial tissue, the contents of NADPH, HK2 and PFKFB3 in serum, and the protein expression levels of HIF-1α, PKM2 and LDHA in synovial tissue were increased (all P<0.05) in the model group. Compared with model group, the circumference of knee joint was significantly decreased (P<0.05), the pain threshold was significantly increased (P<0.05)；in synovial tissue, the pathological score was decreased (P<0.05)；the positive expressions of TNF-α, IL-1β, IL-6 and IL-17 in synovial tissue were decreased (P<0.05), the lactic acid content in synovial tissue was decreased (P<0.05)；the contents of NADPH, HK2 and PFKFB3 in serum and the protein expression levels of HIF-1α, PKM2 and LDHA in synovial tissue were decreased (P<0.05) in inhibitor group and HRN group. Compared with the inhibitor group, the synovial pathological score was significantly increased (P<0.05), positive expressions of TNF-α, IL-1β, IL-6 and IL-17, the content of lactic acid in synovial tissue, the contents of NADPH, HK2 and PFKFB3 in serum, and the protein expression levels of HIF-1α, PKM2 and LDHA in synovial tissue were increased (all P<0.05) in HRN group. HRN can increase the pain threshold, reduce the knee circumference and inhibit the inflammatory response in rabbits with cold syndrome of RA. The possible mechanism is related to the down-regulation of HIF-1α and glycolysis activity.

Expression Regulation of Gluconeogenesis Related Genes in Ovine Skeletal Muscle Cells.

Under fasting conditions, the pathway converting gluconeogenesis precursors into muscle glycogen becomes crucial due to reduced glycogen reserves. However, there is limited research on skeletal muscle gluconeogenesis and the impact of fasting on gluconeogenic gene expression. Sheep fetal skeletal muscle cells cultured in vitro were used to study the effects of varying lactic acid concentrations (0 to 30 mM) and 2.5 mM glucose on the expression of gluconeogenesis-related genes after 6 h of fasting. The effects on mRNA and protein expression of key genes involved in skeletal muscle gluconeogenesis were measured by quantitative real time polymerase chain reaction (qRT-PCR), immunofluorescence, and western blotting at 48 h. Fasting increased the expression of key gluconeogenic genes, fructose-1,6-bisphosphatase 2 (FBP2), glucose-6-phosphatase 3 (G6PC3), pyruvate kinase M (PKM), monocarboxylate transporter1 (MCTS1), glucose transporter type 4 (GLUT4), pyruvate carboxylase (PC), and lactate dehydrogenase A (LDHA). The mRNA levels of FBP2, G6PC3, and MCTS1 significantly decreased with glucose addition. Additionally, 10 mM lactic acid significantly promoted the expression of FBP2, PC, MCTS1, LDHA, GLUT4, and PKM while inhibiting phosphoenolpyruvate carboxykinase (PEPCK) expression. At the protein level, 10 mM lactic acid significantly increased FBP2 and PKM protein expression. This study shows that fasting regulates key gluconeogenic gene expression in sheep skeletal muscle cells and highlights the role of lactic acid in inducing these gene expressions.

Effects of fruit and vegetable waste addition on corn stalk silage quality.

In this study, we explored the effect of fruit and vegetable waste addition on the quality of corn stalk silage. Corn stalks were ensiled 20 days after ear harvesting and mixed with fruit and vegetable waste (FVW) consisting of apple, orange, broccoli, and Chinese cabbage waste as 3% of fresh matter. Fruit waste consisted of solid residue obtained after juicing, and vegetable waste was collected from farms and cut into small pieces (2 to 3 cm). The materials were stored anaerobically in 20-L silo buckets and opened after 60 days of fermentation. There were significant differences in dry matter (DM), acid detergent fiber (ADF), neutral detergent fiber (NDF), total digestible nutrient (TDN), and relative feed value (RFV) levels in FVW derived from all tested raw materials (p<0.05). Corn stalk mixed with orange waste (CSOW) had the highest DM content (28.77%), lowest ADF and NDF content (47.78% and 26.62% of DM, respectively), and highest TDN and RFV content (69.21 and 133, respectively). After 60 days, there were significant differences in all chemical parameters examined (p<0.05). Corn stalk mixed with broccoli waste (CSBW) had the lowest DM loss (2.23%), and the CSOW group had the lowest NDF and ADF content and highest in vitro DM digestibility. CSBW had the lowest pH and ammonia nitrogen content, but the highest lactic acid/acetic acid ratio among the treatment groups. CSOW had the highest lactic acid content (2.27% of DM). The microbial contents of each group differed only in lactic acid bacteria counts before and after ensiling, showing a slight increase (p>0.05) and significant decreases in yeast and mold counts (p<0.05) after ensiling. These findings confirmed that mixing various FVW materials, particularly orange waste, with corn stalks improved the nutritional value of silage. Adding broccoli waste resulted in better fermentation quality than the addition of other FVW materials.

Exploring the influence and mechanism of different frying methods on the flavor quality of low-salt sour meat

To obtain nutritious, healthy, and flavor-enriched sour meat products, the effects of different frying methods (microwave, air-frying, and traditional frying) on the flavor quality of low-salt sour meat were evaluated using metabolomics and other flavor analysis techniques. The pH value of the sour meat rose dramatically, while the TBARS value dropped significantly after frying. E-nose and E-tongue results showed that air-frying could reduce acidity and improve umami. The comprehensive analysis of all samples revealed the identification of 107 volatile flavor compounds, including 10 unique aroma compounds that were specifically detected in the AF group. Additionally, the air frying process notably increased the free amino acid and nucleotide concentrations in sour meat by 53.58% and 159.29%, respectively, while causing a significant reduction in both fatty acid and lactic acid content by 22.84% and 49.29%, respectively. All three frying methods altered the flavor of the samples, but air frying performed better in terms of flavor and texture.

Effects of selenium enrichment on fermentation characteristics, selenium content and microbial community of alfalfa silage

BackgroundSelenium is essential for livestock and human health. The traditional way of adding selenium to livestock diets has limitations, and there is a growing trend to provide livestock with a safe and efficient source of selenium through selenium-enriched pasture. Therefore, this study was conducted to investigate the effects of selenium enrichment on fermentation characteristics, selenium content, selenium morphology, microbial community and in vitro digestion of silage alfalfa by using unenriched (CK) and selenium-enriched (Se) alfalfa as raw material for silage.ResultsIn this study, selenium enrichment significantly increased crude protein, soluble carbohydrate, total selenium, and organic selenium contents of alfalfa silage fresh and post-silage samples, and it significantly decreased neutral detergent fiber and acid detergent fiber contents (p < 0.05). Selenium enrichment altered the form of selenium in plants, mainly in the form of SeMet and SeMeCys, which were significantly higher than that of CK (p < 0.05). Selenium enrichment could significantly increase the lactic acid content, reduce the pH value, change the diversity of bacterial community, promote the growth of beneficial bacteria such as Lactiplantibacillus and inhibit the growth of harmful bacteria such as Pantoea, so as to improve the fermentation quality of silage. The in vitro digestibility of dry matter (IVDMD), in vitro digestibility of acid detergent fibers (IVADFD) and in vitro digestibility of acid detergent fibers (IVNDFD) of silage after selenium enrichment were significantly higher than those of CK (p < 0.05).ConclusionThis study showed that the presence of selenium could regulate the structure of the alfalfa silage bacterial community and improve alfalfa silage fermentation quality. Selenium enrichment measures can change the morphology of selenium in alfalfa silage products, thus promoting the conversion of organic selenium.

Study on Enhancement of Acid Production by Combination Fermentation of Caproic Acid-producing Bacteria and Lactic Acid-producing Bacteria

A new caproic acid bacteria 20-5 (Caproicibacterium sp.) was newly screened in the laboratory, and several high-quality lactic acid bacteria A2-3 ( Sporolactobacillus fermentans ), GCB-3 ( Pediococcus acidilactici ), KR-4 ( Lactiplantibacillus plantarum ), LY-5 ( Levilactobacillus brevis ), B2-1 ( Lactiplantibacillus plantarum ) were used for exploratory compound fermentation experiments. The compound fermentation was a caproic acid bacteria (20-5) alone plus four lactic acid bacteria ( A2-3, GCB-3, KR-4, LY-5, B2-1 ), the experimental ratio was set up four groups of compound ratio of 1 : 2,1 : 1,5 : 1,10 : 1. The optimum ratio of 20-5 to B2-1 was 10 : 1, and the total acid yield reached 26.75 g / L. The best caproic acid production capacity after compounding was the 10: 1 group of 20-5 and B2-1, and the caproic acid yield was 7.22 g / L. The average lactic acid content in the fermentation broth was 4.52 g / L after compounding. After compounding, the acid production of the 1 : 1 and 5 : 1 groups of 20-5 : A2-3 and the 10 : 1 group of 20-5 : B2-1 increased compared with that of single bacteria. In the other compound groups, the acid production capacity decreased after the compound operation, and the lactic acid production generally decreased, but the caproic acid production increased, indicating that caproic acid bacteria can use lactic acid as a carbon source for fermentation and acid production activities, so that caproic acid bacteria can produce caproic acid.

Formic acid enhances whole-plant mulberry silage fermentation by boosting lactic acid production and inhibiting harmful bacteria.

Mulberry has also been regarded as a valuable source of forage for ruminants. This study was developed to investigate the impact of four additives and combinations thereof on fermentation quality and bacterial communities associated with whole-plant mulberry silage. Control fresh material (FM) was left untreated, while other groups were treated with glucose (G, 20 g/kg FM), a mixture of Lactobacillus plantarum and L. buchneri (L, 106 CFU/g FM), formic acid (A, 5 mL/kg FM), salts including sodium benzoate and potassium sorbate (S, 1.5 g/kg FM), a combination of G and L (GL), a combination of G and A (GA), or a combination of G and S (GS), followed by ensiling for 90 days. Dry matter content in the A, S, GA, and GS groups was elevated relative to the other groups (p < 0.01). Relative to the C group, all additives and combinations thereof were associated with reductions in pH and NH3-N content (p < 0.01). The A groups exhibited the lowest pH and NH3-N content at 4.23 and 3.27 g/kg DM, respectively (p < 0.01), whereas the C groups demonstrated the highest values at 4.43 and 4.44 g/kg DM, respectively (p < 0.01). The highest levels of lactic acid were observed in the GA and A groups (70.99 and 69.14 g/kg DM, respectively; p < 0.01), followed by the GL, L, and GS groups (66.88, 64.17 and 63.68 g/kg DM, respectively), with all of these values being higher than those for the C group (53.27 g/kg DM; p < 0.01). Lactobacillus were the predominant bacteria associated with each of these samples, but the overall composition of the bacterial community was significantly impacted by different additives. For example, Lactobacillus levels were higher in the G, A, and GA groups (p < 0.01), while those of Weissella levels were raised in the L, GL, and GS groups (p < 0.01), Pediococcus levels were higher in the A and GA groups (p < 0.01), Enterococcus levels were higher in the G and S groups (p < 0.01), and Lactococcus levels were raised in the S group (p < 0.01). Relative to the C group, a reduction in the levels of undesirable Enterobacter was evident in all groups treated with additives (p < 0.01), with the greatest reductions being evident in the A, S, GA, and GS groups. The additives utilized in this study can thus improve the quality of whole-plant mulberry silage to varying extents through the modification of the associated bacterial community, with A and GA addition achieving the most efficient reductions in pH together with increases in lactic acid content and the suppression of undesirable bacterial growth.

Lactobacillus cocktail and cellulase synergistically improve the fiber transformation rate in Sesbania cannabina and sweet sorghum mixed silage

BackgroundElucidating the mechanism of fiber transformation underlying microbial metabolism is critical for improving fiber-rich silage digestibility and preserving silage energy for ruminant nutrient absorption. However, few studies have combined quantitative microbial function and transformation products in silage to explain this mechanism. Here, we constructed a workflow to detect the substrates and products of fiber transformation in mixed silage of Sesbania cannabina and sweet sorghum (SS) and combined the absolute quantification 16S rRNA sequencing to reveal this mechanism.ResultsThe synergistic effect of Lactobacillus cocktail and cellulase (LC) simplified the microbial diversity and minimized the microbial quantity, making Lentilactobacillus buchneri the dominant species in SS silage. As a result, the LC-treated silage had greater lactic acid content, lower pH value, and less NH3-N content. The indigestible fibers were significantly decreased due to the synergistic effect of the Lactobacillus cocktail and cellulase. Changes in microbial structure during ensiling also resulted in metabolic alterations. The increased levels of microbial enzymes, including β-glucosidase and sucrose phosphorylase, involved in starch and sucrose metabolism led to the enrichment of monosaccharides (including glucose, xylose, mannose, galactose, ribose, rhamnose, and arabinose) in the LC-treated silage. We found that L. buchneri was positively associated with β-glucosidase and sucrose phosphorylase, reflecting the crucial contribution of L. buchneri to fiber decomposition in SS silage.ConclusionUsing an absolute quantitative microbiome, we found that LC treatment decreased the microbial biomass in SS silage, which in turn promoted the energy preservation in the SS silage. The cooperative interaction of the Lactobacillus cocktail and cellulase improved the fiber decomposition and in vitro dry matter digestibility rate by changing the microbiome structure and function in the SS silage, providing guidance and support for future fiber-rich silage production in the saline-alkaline region.Graphical

Utilisation of Lactiplantibacillus plantarum and propionic acid to improve silage quality of amaranth before and after wilting: fermentation quality, microbial communities, and their metabolic pathway.

The aim of this study was to investigate the effects of Lactiplantibacillus plantarum (L. plantarum) and propionic acid (PA) on fermentation characteristics and microbial community of amaranth (Amaranthus hypochondriaus) silage with different moisture contents. Amaranth was harvested at maturity stage and prepared for ensiling. There were two moisture content gradients (80%: AhG, 70%: AhS; fresh material: FM) and three treatments (control: CK, L. plantarum: LP, propionic acid: PA) set up, and silages were opened after 60 d of ensiling. The results showed that the addition of L. plantarum and PA increased lactic acid (LA) content and decreased pH of amaranth after fermentation. In particular, the addition of PA significantly increased crude protein content (p < 0.05). LA content was higher in wilted silage than in high-moisture silage, and it was higher with the addition of L. plantarum and PA (p < 0.05). The dominant species of AhGLP, AhSCK, AhSLP and AhSPA were mainly L. plantarum, Lentilactobacillus buchneri and Levilactobacillus brevis. The dominant species in AhGCK include Enterobacter cloacae, and Xanthomonas oryzae was dominated in AhGPA, which affected fermentation quality. L. plantarum and PA acted synergistically after ensiling to accelerate the succession of dominant species from gram-negative to gram-positive bacteria, forming a symbiotic microbial network centred on lactic acid bacteria. Both wilting and additive silage preparation methods increased the degree of dominance of global and overview maps and carbohydrate metabolism, and decreased the degree of dominance of amino acid metabolism categories. In conclusion, the addition of L. plantarum to silage can effectively improve the fermentation characteristics of amaranth, increase the diversity of bacterial communities, and regulate the microbial community and its functional metabolic pathways to achieve the desired fermentation effect.